1. Field of the Invention
The field of the present invention is acceleration detecting systems of a type having a base plate made of non-conductive material and mounted on a moving object, a stationary contact fixedly disposed on the base plate and electrically connected to a first connecting terminal, and a movable contact cooperating with the stationary contact to constitute an acceleration detecting switch, the movable contact being floatingly supported on the base plate in an opposed relation to the stationary contact and electrically connected to a second connecting terminal, the stationary contact being electrically connected to the second connecting terminal through a resistor element.
2. Description of the Prior Art
Such a system is conventionally known from Japanese Utility Model Application Laid-open No. 40142/89.
In the above prior art system, the movable contact is disposed in an opposed relation to a plate-like stationary contact to constitute the acceleration detecting switch, and the stationary and movable contacts are interconnected through the resistor element which is in parallel to the switch in order to detect a failure of conduction in an energizing circuit including the switch. With such a construction, a weak current can be permitted to flow through the resistor element by energization of the energizing circuit when the switch is opened, and by detection of the weak current, it can be detected whether or not there is a failure of conduction in the energizing circuit. On the energizing circuit a failure of conduction can occur at a coupled portion or junction of the stationary contact. In the above prior art system, a weak current can be permitted to flow through the resistor element even if a failure at the coupled portion of the stationary contact occurs. However, it is impossible to detect the occurrence of the failure of conduction at the coupled portion of the stationary contact.